N.Y. - Helen Slottje first came across natural gas drilling leases in 2007 while helping her brother-in-law search for a small farm to buy in upstate New York. She knew almost nothing about such leases. After all, her previous work as a lawyer back in New Hampshire and Boston had focused on bankruptcy, failing banks and commercial real estate.

But the more she learned about the gas drilling technique of hydraulic fracturing, or hydrofracking, the more concerned she became. New York officials were considering opening the state to gas companies that were using leases to gain drilling rights on hundreds of thousands of acres.

Becoming a quick study in state mining law, Slottje developed a legal theory that contradicted what was then commonly accepted as fact - that if the state approved and regulated fracking, local governments would have no choice but to allow it everywhere, like it or not.

Now, 74 towns across the state's potential gas-drilling region of the Marcellus Shale have adopted fracking bans based on her idea that local zoning codes can bar such "heavy industrial" uses regardless of what the state does. An additional 86 towns have supporters advocating a zoning ban, and 99 towns have enacted moratoriums while waiting to see what happens.

Grassroots zoning bans in two towns have survived legal challenges in two lower state courts filed by industry and pro-fracking landowners. Appeals of those cases are pending before the state's highest court with a decision expected in a few months. Meanwhile, the state of New York has yet to render a decision on whether or when to allow fracking.

Slottje's legal advice, provided free to towns that want it, has made her the North American winner of the prestigious $175,000 Goldman Environmental Prize, awarded annually by the San Francisco foundation of the late Richard and Rhoda Goldman. Six winners globally are selected annually by an international jury, and they will be honored Monday in San Francisco.

The others are a South African who saved a community from toxic waste, an Indian man who organized villagers against industrial pollution, a Peruvian who led a fight to protect indigenous people from dam builders, a biologist who protected habitat for the endangered Sumatran rhino and a Russian zoologist who exposed government exploitation of sensitive habitat.

Suren Gazaryan, 39, Krasnodar, Russia

Gazaryan is a zoologist who organized protests to stop construction and illegal logging around the caves in Russia's Krasnodar region, a wilderness area along the Black Sea that is famous both as a uniquely diverse ecosystem and a popular vacation spot for wealthy Russians.

In the 1990s, Gazaryan worked with the group Environmental Watch on North Caucasus to stop the logging. But he kept discovering new construction and logging, including the clearing of federally protected land for a lavish palace for then president Dmitry Medvedev.

Gazaryan organized protesters to block bulldozers, collected tens of thousands of signatures, authored hundreds of blog posts, shared video footage of illegally seized land on YouTube and held demonstrations across the country. In 2009, the government created the 25,000-acre Utrish Reserve along the northwest coast of the Black Sea, and the plans for the presidential palace were abandoned.

Gazaryan's good deeds did not go unpunished. He was convicted in 2012 of organizing a public rally against the illegal seizure of protected forestland for a governor's mansion. That year he was charged with attempted murder of security guards at another illegal development, this one allegedly by current President Vladimir Putin. Facing a prison sentence, Gazaryan fled to Estonia, where he remains in exile.

Ruth Buendia Mestoquiari, 37, Ene River Valley, Peru

Buendia is an Ashaninka Indian who successfully fought an energy company's plans to build a dam along the Ene River, flooding out the remaining indigenous communities. She organized the Ashaninka to campaign against the proposed Pakitzapango Dam, which had been rushed through without any input from the indigenous people in violation of the law. In 2010, the Peruvian Ministry of Energy rejected a request to allow the Pakitzapango to go forward. The primary shareholder backed out the next year as a direct result of Buendia's campaign.

Rudi Putra, 36, Aceh, Indonesia

Putra, a conservation biologist, is an expert on the Sumatran rhino, the smallest and most critically endangered member of the rhinoceros family. He has led many expeditions tracking down poachers in the Leuser Ecosystem, a 6.4 million-acre forest and one of the last places where the Sumatran rhino lives. But Putra realized during these expeditions that habitat destruction from illegal palm oil plantations was just as big a problem as poaching.

He began a one-man campaign to fight deforestation, urging police and local officials to enforce laws against forest clearing. He began educating families about the fresh water and flood protection benefits of an intact forest.

Putra's efforts led to the elimination of 1,200 acres of illegal palm oil plantations in the Leuser Ecosystem and the re-creation of a lost wildlife corridor that has helped Sumatran rhino populations increase over the past decade.

Putra is now fighting a plan by the Aceh provincial government to open large tracts of forest in the Leuser Ecosystem to palm oil development. The online petition he circulated in 2013 was signed by 1.4 million people and has prompted individuals and governments around the world to join his campaign.

Desmond D'Sa, 57, Durban, South Africa

D'Sa was 15 when the apartheid South African government uprooted his family and relocated them to south Durban to work at a chemical plant, one of the more than 300 agrochemical plants, oil and gas refineries that polluted the region. The area, which was populated by mostly low-income and working-class families, became known as "cancer valley" because of the high cancer rate.

D'Sa was appalled in 1990 when Wasteman, a large waste management company, built a hazardous materials plant. The plant's trucks drove through neighborhoods where they regularly spilled toxic waste. The chemicals leached into the ground and contaminated the groundwater.

D'Sa, who co-founded the South Durban Community Environmental Alliance, led a campaign against Wasteman starting in 2009 when the company applied to expand its lease. D'Sa organized mass demonstrations and exposed illegal trucking of waste material. The demonstrations were so effective that in November 2011 Wasteman shut down the landfill and ceased all operations. The work came with a cost. D'Sa's home was firebombed, causing him and his wife to be hospitalized. He is now fighting the $10 billion expansion of Durban's port, which he claims would displace thousands of residents and exacerbate the pollution problems.

Ramesh Agrawal, 56, Raigarh, India

Agrawal, a former social worker, owned and operated an Internet cafe when he learned that Jindal Steel and Power Ltd. was planning to build a giant coal mine in nearby Chhattisgarh, where almost one-fifth of India's coal reserves are buried. He had seen villagers displaced by rampant industrialization and decided to help protect the people from exploitation.

Agrawal founded Jan Chetana, a grassroots movement, and used his Internet skills to look up documents. In 2008, he organized residents against the coal mine, which was planning to burn 4 million tons of coal a year. He filed numerous petitions and exposed Jindal's failure to hold public hearings or obtain environmental clearances according to the law.

In 2012, the National Green Tribunal revoked the coal plant's permits, citing the violations cited in Agrawal's petitions. For his trouble, gunmen broke into his home and shot him in the leg, shattering bones. Agrawal is recovering from his wounds, but he has continued from his bed to help villagers in Chhattisgarh fight exploitation by landowners and coal companies.